Objective: compare outcomes of unstable intertrochanteric hip fractures treated with two commercially available implants. Design: retrospective observational cohort of 288 treated with a Gamma® nail and 398 with an InterTAN® nail. Patients were operated between 1997 and 2010. Primary outcomes: satisfactory reduction, optimal cephalic screw placement, and to evaluate the incidence of mechanical complications; secondary measures included the tip-apex distance (TAD), hematocrit (Hto) and hemoglobin (Hb) drop, transfusion requirement and volume, hospital length of stay and the time to first ambulation.

Rationale: to evaluate whether outcomes differ between two commonly used cephalomedullary nails for unstable intertrochanteric hip fractures in routine practice.

Setting: double-centre, single-city retrospective cohort with consecutive patients treated by the same surgeon-Gamma2® at the Hospital Clínico Universitario (1997-2002; n=288) and InterTAN® at Vithas Hospitals (2002-2010; n=398). Cohorts: defined by the implant used in usual care; adults ≥65 years with unstable AO/OTA A2-A3 patterns were included; key exclusions were stable patterns, pathologic fractures, subtrochanteric extension, poor radiographs, and <6-month follow-up. Planned analyses: between-group comparisons of reoperation and implant-related complications (primary focus), plus perioperative and functional parameters, using χ²/t-tests as appropriate adjusting for age, sex, ASA class, AO/OTA pattern, reduction quality, and screw position metrics (e.g., TAD); results reported as effect sizes with 95% CIs, with sensitivity analyses by fracture pattern and reduction quality

Inclusion Criteria:

• Unstable trochanteric fractures confirmed radiographically according to OTA (Orthopedic Trauma Association), treated with Gamma or InterTAN nail,
• available follow-up for ≥ 6 months

Exclusion Criteria:

• Pathological fractures
• Polytrauma precluding standard treatment/follow-up
• Missing key variables/outcomes

Patients who received the Gamma nail (288) underwent surgery at the Hospital Clínico Universitario, Valencia (1997-2002). On the other hand, the patients operated upon the InterTAN nail (398) underwent surgery at the Vithas Hospitals Group in Valencia between January 2002 and December 2010.